I had the chance of picking up a copy of Brad Lackey's training book. Though written in about 1983, the year after his 82 world championships, much of the matrerial is sound even by todays standards. Of particular irony was a chapter devoted to jumping. Double's were just becoming in vogue and Lackey addresses these offering advice that would safely get you over smaller doubles. The only real difference between what is advocated today and what ZLackey deems appropriate is his advice on keeping the elbows low. Nonetheless, if yoou can find a copy, buy it. The pictures of bikes from the seventies and early eighties is worth it.